Yes

you do need a jacket based on the weather in Pacifica, CA, USA 1 second ago

Why? Because it's bitterly cold.
48°F9°C & Mostly Cloudy

Wind is 5 mph8 km/h from the SW, gusting to 9 mph14 km/h
March 29
4am48°F9°C6 mph9 km/h SWCloudy
5am48°F9°C6 mph10 km/h SWCloudy
6am49°F9°C6 mph10 km/h SCloudy
7am48°F9°C7 mph11 km/h SCloudy
8am49°F9°C7 mph12 km/h SCloudy
9am49°F9°C8 mph14 km/h SDrizzle
10am48°F9°C9 mph15 km/h SDrizzle
11am48°F9°C11 mph17 km/h SDrizzle
12pm48°F9°C12 mph19 km/h SEDrizzle
1pm49°F10°C14 mph23 km/h SEDrizzle
2pm50°F10°C16 mph26 km/h SEDrizzle
3pm50°F10°C17 mph28 km/h SERain
DateLowHighWindDayNight
March 2948°F9°C53°F12°C15 mph25 km/h from SERainDrizzle
March 3047°F8°C58°F14°C9 mph15 km/h from NEDrizzlePartly Cloudy
March 3148°F9°C58°F14°C8 mph13 km/h from WPartly CloudyMostly Clear
April 148°F9°C63°F17°C5 mph7 km/h from NWClearClear
April 250°F10°C62°F17°C5 mph8 km/h from WMostly ClearMostly Cloudy
April 350°F10°C59°F15°C11 mph18 km/h from WMostly CloudyWindy
April 447°F8°C54°F12°C19 mph31 km/h from NWWindyPartly Cloudy

Yes

Low of 47°F9°C, High of 57°F14°C
Wind: 9 mph15 km/h
Precipitation: 65% rain

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